Described below are a method for determining a thickness of rolling stock, in particular a rolling strip or a metal plate and a device for determining a thickness of such rolling stock.
In process lines, such as for example in rolling mills, thickness measurements based on the penetration of the material to be measured by radiation, for example gamma radiation or X-ray radiation, are predominantly used. The measurement of thickness using rays is based on the effect that radiation is partially absorbed when penetrating material. To this end, the beam of a radiation source is directed perpendicularly onto the material to be measured. When the density of the material to be measured is known, the thickness of the material to be measured is determined at this point with the aid of the law of absorption. In order to obtain measurement results having a very high level of accuracy, many factors and parameters do however need to be known, for example alloying constituents, temperature of the material to be measured, etc. The values are made available to the measurement device. In the case of different compositions of a material to be measured at different points in the material, if the composition is not precisely known or in the case of fluctuations in the temperature of the material to be measured the thickness measurement can therefore deliver inaccurate measurement results.
An alternative method for thickness measurement is to ascertain the thickness of the material to be measured by way of its weight. For this purpose, samples of the material to be measured must be taken which are evaluated in the laboratory. This course of action is time-consuming and results in disrupted production.